Most people tend to think of image stabilization as being mainly for telephoto lenses. While it's true that their longer focal lengths tend to magnify the effects of camera shake, image stabilization can provide a very useful assist at wider angle focal lengths as well; anyone who's ever tried to blur the image of a waterfall, while keeping the surrounding landscape tack-sharp knows exactly what I'm talking about.

At the 55mm end, Canon's IS image stabilization system works pretty well, offering around three stops of hand-holding stability. Unsurprisingly, we get 100% hand-holding sharpness at the 1/60s mark with IS turned off, but with IS turned on, that stability goes as slow as 1/8 of a second.

Mouse over this chart to show results with IS activated.

Performance at the 250mm end is very good, offering four stops of hand-holding stability: here we have 100% hand-holding sharpness at 1/125s, but we get almost 100% hand-holding sharpness at 1/8s with IS engaged.

Mouse over this chart to show results with IS activated.

IS systems tend to provide more benefit to less-stable shooters than very steady ones, so most users will see the same or greater amounts of shake reduction as we measured here. You can read more about our IS test methodology here: SLRgear IS Test Methodology, v2.